case%utkvx4.DECNET@UTKCS2.CS.UTK.EDU (J. D. CASE) (10/29/87)
in reply to mead@tut.cc.rochester.edu Ted: >The interfaces in the p4200 send out a maintenance packet with an Ethernet >address of 02-07-01-00-00-00. This packet is sent with a CRC error and is >apparently used to verify operation of the interface. Yes, I believe you are correct. >These packets cause the "Bad Frame" counter on RBMS to increase steadily >(about once or twice every four seconds). We see the same effect. >We are also experiencing some >problems with a host trying to establish a DECNET connection, that is on >the same side of the LAN Bridge as the p4200. I do not believe the bogus packets generated by the p4200 are related to your decnet problem. We have multiple decnet hosts on the same segment as the 4200 which can establish decnet connections with each other and through bridges to decnet hosts on other segments. >Does anyone know whether the RBMS "Bad Frame" counter is a "dummy" counter >[its value has no effect on the protocol]? If the counter really does have >some implication on a higher level protocol, what might that be? I think you ought to look somewhere else. The only caveat is that our 4200 does not do decnet -- it only does ip. your situation may be different (i can't tell) and may lead to other conclusions. The only problem we have had from the test packet emitted from the 4200 is that it makes using lb100 counters useless as measures of the signal-to-noise ratio on a cable regards, jdc